Paper machinery



3 Sheets-Sheet 1 Original Filed Dec. 29 1951 INVENTOR.

JOSEPH BAXTER JR.

W M w W ATTORNEYS J. BAXTER, JR

PAPER MACHINERY March 28, 1961 3 Sheets-Sheet 2 Original Filed Dec. 29, 1951 PREsuRE SWITCH REVER'SING- SWITCH INVENTOR.

JOSEPH BAXTER JR.

AT TORNE YS March 28, 1961 J. BAXTER, JR

PAPER MACHINERY 3 SheetsSheet 3 Original Filed Dec. 29, 1951 INVENTOR JOSEPH BAXTER JR WMZW' ATTORNEYS United States Patent PAPER MACHINERY Joseph Baxter, Jr., Franklin, Ohio, assignor to The Blackglhaiwson Company, Hamilton, Ohio, a corporation of Original application Dec. 29, 1951, Ser. No. 264,088,

now Patent No. 2,760,411, dated Aug. 28, 1956. Divided and this application Apr. 25, 1956, Ser. No. 580,595

2 Claims. (Cl. 162-273) This invention relates to a Fourdrinier paper machine. This application is a dvision of my application Serial No. 264,088, filed December 29, 1951, now Patent No. 2,760,- 411, issued August 28, 1956.

The invention has special relation to the control of tension in the Fourdrinier wire, from the standpoint both of facilitating wire changing and also of maintaining controlled tension in the Wire during operation, and one of the objects of the invention is to provide a Fourdrinier paper machine having an adjustable tensioning device for the wire which incorporates a continuously operable control for measuring the tension in the wire and a drive automatically responsive to the measuring control in such manner as to correct during operation of the machine for variations in tension from a desired maintained sub stantially constant tension.

An additional object is to provide an automatic tension controlling device for the Wire of a 'Fourdrinier paper machine which is constructed and arranged for ready shifting between an operating position wherein it establishes and maintains desired tension in the wire and a release position such that not only is it free of the wire but also in its movement to the release position, it provides suflicient slack in the wire for ready removal and changing thereof without requiring the release or removal of other parts of the machine.

Other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.

In the drawings:

Fig. 1 is a side elevational view illustrating the wire accordance with the present invention;

Fig. 2 is a section on the line 2--2 of Fig. 1 showing the arrangement of stretch rolls for tensioning the forming wire;

'Fig. 3 is a fragmentary and somewhat diagrammatic section of a Fourdrinier paper machine constructed in v view in the nature of a perspective showing a drive for the stretch rolls;

Fig. 4 is a fragmentary view on a larger scale showing the position of the stretch rolls during operation of the machine; i

Fig. 5 is a view similar to Fig. 4 showing the position of the stretch rolls during wire changing;

Fig. 6 is a further enlarged fragmentary view showing a detail of the stretch roll mechanism;

Fig. 7 is a perspective view of the wire section of a Fourdrinier machine embodying a modified construction in accordance with the present invention;

Fig. 8 is a fragmentary view looking from right to left in Fig. 10 and partly broken away showing a portion of the wire tensioning mechanism of the machine of Fig. 7; and

Figs. 9 and 10 are diagrammatic views in side elevation illustrating the operation of the wire tensioning mechanism of Fig. 8. I

Referring to the drawings, which illustrate preferred -embodiments of the invention, Fig. 1 showsthe general 6 2,976,924 Patented Mar. 28, 1961 arrangement of the-wire section of a Fourdrinier paper machine including the continuous forming wire 30, the breast roll 31, table rolls 32 provided with water deflectors 33, suction boxes 34 and the suction couch roll 35. The stock inlet or slice is indicated fragmentarily at 36, and similarly the usual forming board and its saveall tray are indicated at 37 and 38 respectively. 1

The main frame structure supporting the breast and table rolls is described in detail in my above Patent No. 2,760,411. It includes a plurality of truss members 40 which extend transversely of the direction of wire travel in spaced relation longitudinally of the machine, and each truss member '40 has a supporting post 42 at the back of the machine. A covering roof 55 of stainless steel or other suitable sheet material is supported on these truss members and is formed of curved section'with its side portions inclined downwardly in overhanging relation with the end of the truss members.

The supporting structure of the machine includes a pair of base members 60 and 61 which extend along the front and back of the machine similarly to the usual sole plates'but which are shown as formed of generally trough shape in section to receive water draining from the sides of the roof 55, and each base member ha a plurality of openings 62 for directing water therefrom into the usual wire pit (not shown). The rear base member 61 includes a plurality of rib-like stand portions 65, and the posts 42 at the back of the machine are supported at their lower ends on a shaft 66 journaled in these stands 65 and extend the full length of the machine. Pivotal movement of the frame on the shaft 66 for wire changing is effected by fluid pressure cylinders 70 mounted at the back of an up-standing portion of each of the stands 65, each having a piston rod connected with the adjacent post 42. The arrangement is such that when pressure is applied to cylinder 70, the posts 42 are pulled rearwardly of the machine so that the entire main frame rocks with the shaft 66, and the frame may be readily held in the resulting raised position by means such as a loopshaped latch member pivoted to each stand 65 and operated by a fluid pressure cylinder 77 for engagement and disengagement with the cooperating latch portion at the upper end of the adjacent post 42.

Fig. 1 shows the general location of the several guide rolls for the lower run of the wire 30. The guide roll is mounted below the wire, and one or more inside rolls 88 above the lower run of the wire are carried by the main frame structure for tilting with the truss roof. The guide roll 90 next to the couch is also an inside roll and iscarried by supports 91 extending downwardly from one of the suction boxes 34 and tiltable therewith. This provides the important advantage in operation that the wire passes below roll 90 after leaving the couch roll so that any particles of fiber adhering thereto tend to be forced out. This cleaning action is further aided by show- I em 95 located between roll 90 and the couch roll which promote effective cleaning by maintaining a flooded condition at the nip of roll 90 and the wire.

Figs. 2-6 illustrate the construction and operation of the stretch roll arrangement which maintains proper tension in the wire 30 during operation of the machine and also provides slack in the wire for changing. The

two stretch rolls and 131 are journaled in a pair of arms 132 and 133 supported at opposite sides of the machine between guide rolls 85 and 88. The arm 132 at the front of the machine is fixed at approximately its center to a shaft 135 which is shown as mounted on a stand 136 or may be mounted directly on the base member 60 similarly to the guide roll 85. The arm 133 is similarly mounted for pivotal movement about its center by means of a shaft 137 carried by a stand 138 on base switch member 61. The shaft 135 carries a gear 140 meshing with a large gear 141 on a shaft 142 extending across the width of the machine and shown as mounted on the base members by means of stands 143, and at the back of the machine, the shaft 142 carries a large gear 145 meshing with a gear 146 on shaft 137.

During operation of the machine, the wire 30 wraps both of the stretchrolls 13$ and131 as shown in Figs. 1 and '4. Rotation of arms 132. and 133 will cause roll 13%) to move about the axis of shafts 135 and 137 in a path passing between rolls 8% and 131, and similarly the path of roll 131 will pass between rolls 85 and 139, thus varying the extent of wrap of the wire on the stretch rolls and correspondingly increasing or decreasing-the tension in the wire depending upon the direction of movement of the rolls. A motor operated control is accordingly providedfor eflecting rotation of the stretch roll arms in response to variations of the tension in the wire in order to maintain substantially constant tension. This control includes a motor 155 driving a worm 151 meshing with a worm gear 1'52 mounted for-free rotation on shaft 142. by means of a sleeve or hub portion 153. The sleeve 153 also carries an arm 15- 5 supporting a small air cylinder 155, and the piston rod 156 from cylinder 155 is positioned to abut an arm 157 projecting axially from the gear 341.

it will thus be apparent that if arm 154' moves in clockwise direction as viewed in Fig. 3, it will act through cylinder 155 and rod 1 .56 to force arm 157 and gear 141 similarly in clockwise direction. This movement will be transmitted through gear first to cause counterclockwise 'movement of the stretch roll arms and ti htening .of wire 3t), and correspondingly movement of arm 154 in counter clockwise direction will cause clockwise movement of the stretch roll arms and resulting decrease in the tension of the wire. To control this movement automatically in such manner as to maintain predetermined tension conditions in the Wire, a pressure switch 16%? is provided which is connected with the cylinder 155 as indicated diagrammatically in Fig. 3 and which in turn controls a reversfor motor The switch 16% is adjustable to respond to a change in the pressure in cylinder 155 above or below a predetermined desired rang and since such change wili be caused by increase or de crease of the tension in the wire, transmitted through-the contact between piston rod 156 and arm 157, when a change occurs the motor 55% will be actuated to effect the proper correcting movement of the stretch roll arms.

Figs. 5 and 6 show the operation of the stretch roll mechanism for releasingthe wire for changing. The journals of roll 231 are releasably carried in the arms 132 and 1.332 by means of a releasable bearing .portion 165 pivoted on the arm at led and provided with a reieasabie locking bolt 367, which may also .be pivoted to the arm as shown for easy handling. At each sideof the machine, a'hock li is pivoted at 171 to the machine frame l normally held .inretracted position by a suitable role able latch mechanism indicateddiagrammaticaliy a 2 he hooks 1% are so arranged that when they ed and. dropped to their downwardly hanging positions they are in position to receive the jonrnais f roll 31 as the stretch roll arms rotate. Thus in t release the wire for changing, it ismereiy nece to rotate the arms sufficiently to deposit the journals of roll 131 in hooks 17 t release thebearingportic-us and then continue the movement of-the arms until they are approximately horizontal as shown in Pig. 5. in this position of the parts, the roll 131is sup ported from the cantilevered portion of the machine frame while the roil 13% remains supported on'the base structure, and the wire is accordingly free for lateral movement as shown in Fig. 5. Then after the wire has been removed andre-placed, thereverse operation will'return the stretch roll mechanismto its operating-position shown in Fig. 4.

This tensioning mechanism for the wire oflers outstanding advantages for convenience of wire changing as well as during operation of the paper machine. It is compact and does not require changing of the basic machine frame, and at the same time it provides adequate slack for wire changing without requiring a well or other special structure for receiving the slack after the wire has been tightened on the machine. In addition, since it 'is constructed for adjustment through a comparatively wide range, the initial length of the wire is not critical, and the stretch rolls can be operated to compensate for a range of wire lengthswithout adjustment other than-the required movement of theseirolls to their positiors wherein the desired tension in the wire is established. At the same time, it will be noted that with the parts inthe relative operating positions shown in Fig. 4, the path of the wire from the roll to the adjacent roll v88-is very nearly perpendicular to the'arms .132, and therefore substantially'in line with the effective tensioning movement of the roll 130, and this is the optimum condition for maximum accuracy of measure- -ment of the .wiretension. Furthermore, th arms 132 can move the roll 13% through a considerable angular range to either side of the position shown in Fig. 4 without substantially changing this relationship between it and the wire.

Figs. 7-10 show a modified construction of Fourdrinier machine constructed in accordance with the invention in which special provision is made to cause all the water draining from the web through the table rolls to be'discharged at the back of the machine. The truss roof structure which supports the breast roll and the table rolls includes truss members 3% which are described in detail in my above Patent No. 2,760,411. Each of the truss members Silt) is supported forpivoting movement at the back of the machine, and a leg 315 is securedin depending relation to thefront of each truss member and is adapted to seat on the upper end'of' a-correspondingly spaced base member 316, with the engaging ends of these parts being shown as formed with tongue and groove portions for increased stability, and the lower ends ofthe legs 315are provided with bracing struts 317.

The table roll units 323 and the mounting 324 for the breast roll 325 are described in my-above patent, and a shakemechanism 326 is shown as mounted at the back of the machine and connected'through rods 327 with-"the adjacent shake rail as described in my-above patent. 'The :suction couch T011 328 and its mounting and also the suc ;tio-nbox.indicated generally at 339 are similarly described in my above patent. Atthe front of the machine, suction :box 330 includes a pair of depending legs 331fitting corresponding supporting base members 316, and one 'of-the legs 331 also cooperates with the rearward portion of the "suction box .to support the guide rolls 333. Thele'gs'SlS 'similarly cooperate with the posts 315 to support the pair of first and second guide rolls 335 and f336 -respectively, while the lower: guideroll 337 is supported by fixed stands '338.

The Fourdrinier machine of Fig. 7 also incorporates a modified construction of wire tensioning mechanism in accordance with the invention. Referring particularly to Figs. 8-10, *a'shaft fi' itlissupportedt on the baseof-the machine below the guide roll 335, and this sha'ftextends from .fl'OIllZTiO back of the machine and 'supportsa pair of elongated :curved arms 341 at its-opposite ends which are secured thereto for rotation therewith and in turn carry a stretch roll 343. A worm geari tfi is free on shaft'fatl and is driven by a'worm 346 from a motor 347. The gear .Msiincludes a hub portion 343 which carries an arm 350, and this arm is operatively connected with the adjacentarm 3'41 through a pressure cylinder or'bellows 355 which corresponds structurally-and functionally with the cylinder as described in connection with' 'Fig. 3 and correspondingly controls motor347.

As shown in Fig. 9, the arms 34]. maybe swungdownwardly to a retracted position in which the wire 30' is released for iateral movement between rolls 335 and 343 for changing, and this arrangement does not require release of any of these parts in any other way. During operation of the machine, the arms 341 normally carry the roll 34-3 in approximately the position shown in Fig. in which roll 343 cooperates with roll 335 and the adjacent roll 336 to maintain the proper tension in the wire, with the actual operating position at any given time being controlled by the tension in the wire acting through the pressure unit 351 in the same manner as described in connection with Fig. 3, and Fig. 10 shows that this mechanism also otters the optimum relationship between the direction of wire travel and the tensioning movement of the roll 343 as previously described in connection with Fig. 4. Fig. 10 also shows that in the operating position of these parts, the direction of wire travel between the roll 343 and the fixed guide roll 336 is at substantially right angles to a line connecting the axes of the rolls 343 and 335, which is a further characteristic of the optimum relationship of these three rolls. It will also be noted that since in this arrangement the roll 335 which acts as a stretch roll is also one of the guide rolls and is fixed with relation to the main frame of the machine, it may readily be driven as desired in properly synchronized relation with the couch roll to assist in proper driving of the wire, as by a separate synchronized motor or a belt drive from the couch roll as indicated diagrammatically at 360 in Fig. 9.

While the forms of apparatus herein described'constitute a preferred embodiment of the invention, it is to be understood that the invention is not limited to these precise forms of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. A Fourdrinier paper machine comprising a frame, a traveling continuous forming wire supported on said frame, a first roll and a second roll mounted in spaced relation in said frame on the same side of the wire, a third roll located on the opposite side of the wire from said first and second rolls, mounting means supporting said third roll for swinging advancing and retracting movement toward and away from the wire respectively, said mounting means having a range of said swinging movement providing a predetermined advanced position of said third roll wherein the path of the wire from said third roll to said second roll is at substantially right angles to a line connecting the axes of said third roll and said first roll and wherein also said movement of said third roll is substantially directly in line with the path of the Wire from said third roll to said second roll, reversible drive means for said mounting means, sensing means connected with said mounting means for continuously sensing the torque load thereon caused by the tension in the wire, said sensing means having a neutral position corresponding to a predetermined wire tension, said wire being of predetermined length developing said predetermined tension in response to swinging movement of said third roll to said predetermined advanced position, and means including a reversing switch controlled by said sensingmeans in response to variations .in the wire tension and operative to actuate said drive means to swing said mounting means in the direction to restore said predetermined tension.

2. In a Fourdrinier paper machine having a frame and a traveling continuous forming Wire supported on said frame, apparatus for maintaining the tension in said wire within a predetermined range, comprising a first roll and a second roll mounted in spaced relation in said frame on the same side of the wire, a third roll located on the opposite side of the wire from said first and second rolls,

mounting means supporting said third roll for swinging advancing and retracting movement toward and away from the wire respectively, reversible drive means for said mounting means, sensing means connected with said mounting means for continuously sensing the torque load thereon caused by the tension in the wire, said sensing means having a neutral position corresponding to a predetermined wire tension, and means including a reversing switch controlled by said sensing means in response to variations in the web tension and operative to actuate said drive means toswing said mounting means in the direction to restore said predetermined tension.

References Cited in the file of this patent UNITED STATES PATENTS 51,582,323 Warren Apr. 27, 1926 1,885,163 White Nov. 1, 1932 1,929,852 Reid Oct. 10, 1933 2,521,413 Scheurmann Sept. 5, 1950 r 2,725,976 Madeira Dec. 6, 1955 

